On the evening of Monday, April 15th, the majestic Catholic cathedral of Notre Dame in Paris was engulfed in a raging fire. Within a few hours, the oaks from the main ceiling were torched, and soon enough the collapse of the spire offered a horrifying spectacle to heartbroken Parisians. One of the world’s most iconic monuments has been left deeply scarred, to an extent that – to the date of this article’s drafting – the amount of effective damage has yet to be quantified.

Long before the damage assessment is being finalized, it was clear that the entity of the devastation would be significant. The reconstruction of Notre Dame will surely have an astronomical cost, and a fundraising has started collecting the highest possible amount. To date, the amount is approaching 1 billion Euros, and it is destined to increase. With the French President Macron declaring that the cathedral would be rebuilt within 5 years from now, and given the global exposure of the event, we can expect that a combined focused effort of public donations and tax payer's money will cover the costs.

The role and challenge of insurance

Among the various topics being discussed since the Notre Dame fire occurred, the insurance of historical monuments should certainly pitch our attention. Insurance depends on the owner of the monuments – in Notre Dame's case, the Ministry of Culture. As it often happens, unfortunately the landmark was not insured. These monuments and their content, such as artifacts, specimens and reliefs, are often inestimable, leading to a possibly unbearable amount for both the owner and the insurer. Jad Ariss, Secretary General of the Geneva Association, provided insights as for the insurance industry's viewpoint.During a recent interview, he stated that insuring a monument like Notre Dame would be very difficult from the insurer's side due to the entity of the coverage required. However, he added, depending on the business strategy of the monument owner, it was not impossible. Ariss then concluded that catastrophe bonds should be looked to as a possible option to maximize the coverage for these landmarks.

Data fusion as the gamechanger?

Assuming adequate funds will be collected, and a prompt reconstruction will take place, there are still major technical issues to overcome. Notre Dame has been built over a span of eight centuries, and it has undergone numerous modifications ever since. It would appear that the original project design documents no longer exist. In older times, these records were not considered of long-term relevance. Most techniques employed during those construction phases are no longer used, and even if they were, it would still be challenging to replicate them with the exact visual outcome. The knowledge of the detailed structure of the investigated subject, the used materials, and other relevant characteristics, are all important information that can provide a comprehensive overview on the investigated item. But what happens when holistic detail information of the previous reality is not available anymore? This is when the combination of multiple datasets in a meaningful way (data fusion) comes handy.Data fusion is currently used in a broad variety of fields, including insurance. For instance, in SwissRE's Digital Smart Analytics, we combine contract data with public statistics for loss ratio analysis, weather patterns and twitter to detect flood occurrences or crowd sourced data and satellite data for crop field identification.

Comparably, a similar combination process can be done with information retrieved from monuments and artifacts, if data are available. But the tricky point sometimes is to identify the source of such data. This is where technology comes to our aid, and in this case from the most unexpected avenues as well.

The first source is called Assassin's Creed, a videogame produced by Ubisoft (USA). Its concept is based on the fight between the Assassins, fighters for peace through free will, and the Templars, fighters for peace through (religious) control. The distinctive feature of the game is the climb-and-parkour skills of the protagonists, whichliterally jump from building to building, creating a unique sense of action. This, combined to a very high graphic resolution, made Assassins' Creed extremely successful over the years, leading to the release of numerous chapters. One of them – Assassin's Creed: Unity - took place in Paris.

With the Notre Dame cathedral being a key landmark, it was instrumental to make the setting look as real as possible. To do so, a reliable reproduction of the cathedral was of paramount importance, visualizing the highest possible amount of details. Caroline Miousse, senior level artist at Ubisoft, took care of the visuals. She recreated the Notre Dame cathedral using pictures and videos, without ever having visited the landmark. Miousse recreated the cathedral on an almost 1:1 ratio, burning approximately 5000 hours over a 14 months span 'to make sure that each brick was as it should be'. The result was a realistic video game graphic rendering.

The second source is a high precision laser scan of the Notre Dame cathedral, carried out by the now-passed away art historian Andrew Tallon. Tallon, from Vassar University, was among the pioneers of 3D scanning of historic building to unravel otherwise obscure details on the employed construction techniques. He laser-scanned the surface of Notre Dame, obtaining an accuracy up to 5 mm. The result is a complex – yet, comprehensive – 'point cloud' which depicts the outer surface of the cathedral with a very high level of detail.

Today, the original work from both Tallon and Miousse proves of paramount importance for the reconstruction process of Notre Dame. With the original project sketches being lost, these datasets become an instrumental aid to architects and designers of the inevitably upcoming works. Possibly way more than the two authors may have thought when they carried out their respective work: they have given their data a legacy value.

Future outlook

Pitching Ariss' suggestion, the application of catastrophe bonds around historical landmarks should be considered as a possibility. This should help cover the enormous costs which might incur from events of different nature.

In the case of Notre Dame, it would appear that the existence of this fortuitous dataset would be part an integral part of the future reconstruction process - but still, fortuitous. In the future, we need to be more proactive in this direction, engaging more with public entities to preserve these buildings. The role of the insurers is to make sure that this horrific event sets an example for heritage preservation and resilience provision.

On the tech side, as the field is still under development, there is a major potential to deep dive into heritage preservation possibilities. There are various vendors that perform high precision scanning of large building and small artifacts to a resolution high enough to allow both a detailed scaled 3D printing for rebuilding parts andreconstructing the entire object.

Ubisoft's example teaches us that the origin of data – and the applications of data fusion - can be the most surprising. Gaming industry puts major efforts in the field of data science, and perhaps this can be an avenue to pursue. Clearly, Ubisoft has acknowledged that the stakes in its Assassin's Creed mission go far beyond deliveringa gaming experience, and it is more about legacy. In line with that thought, on April 17th the company announced the donation of 500.000 $ towards Notre Dame's rebuilding process.

It is difficult to propose one way forward, and probably there is no firm line as to how we can insure our heritage. As (re)insurers, aiming to build a digital archive of monuments and landmarks can be a long and costly operation, but possibly a bold, long-term investment. With data fusion proving as a valuable tool to solve complex issues, one should expect this to be more and more versatile and widely used. An all-round collaboration with multiple data providers might support the creation of a digital archive for our heritage, with mutual benefits. Ultimately, this will prove an excellent visibility opportunity, highlighting the commitment of the insurer as a forward-thinking, mindful entity with a strong sense of duty and corporate responsibility towards the community.